Wide temperature zone hydrogen storage material low temperature hydrogen storage performance testing device
Technical field
The present invention relates to a kind of hydrogen storage material low temperature hydrogen storage performance testing device.Particularly a kind of wide temperature zone hydrogen storage material low temperature hydrogen storage performance testing device that uses metal-organic framework materials as hydrogen storage material.Belong to cryogenic engineering and cryogenic technique field.
Background technology
Hydrogen Energy is abundant as a kind of reserves, wide material sources, carbon content are low, green energy resource that the chemical combustion value is high is the ideal substitute of fossil fuel, is 21 century one of main new forms of energy.As a kind of novel clean energy resource, the cheapness of hydrogen is produced, safe and efficient storage and conveying and sizable application are the emphasis problems of current research, and the storage of hydrogen is the Hydrogen Energy key in application, during in particular for motor vehicles, material of main part also must have high quality capacity and volume capacity and easily discharges and characteristics such as can recycle except satisfying economically viable requirement.As for automobile-used hydrogen storage system, the target that International Energy Agency proposes be the quality hydrogen-storage density greater than 5%, the volume hydrogen-storage density is greater than 50kg H
2/ m
3, and hydrogen discharging temperature is lower than 423K, and cycle life is above 1100 times; And the target that USDOE proposes is that the quality hydrogen-storage density is not less than 6.5%, and the volume hydrogen-storage density is not less than 62kgH
2/ m
3, the actual hydrogen storage ability of automobile-used hydrogen storage system is greater than 3.1kg (be equivalent to car travel the required fuel of 500km).And hydrogen storage material can reversibly inhale in a large number and put hydrogen, become a kind of important carrier in the storage of hydrogen and course of conveying.
The hydrogen storage property of hydrogen storage material mainly characterizes with pressure composition temperature (P-C-T) curve.By the P-C-T curve, we can see what, the hydrogen storage properties such as hysteresis phenomenon and Temperature Influence of inhaling the plateau pressure size put hydrogen, sucking/placing hydrogen amount, can also obtain associated hot mechanics and kinetic parameter.This shows that the development of hydrogen storage property test unit has great importance for the research and development of hydrogen storage material.At present, measuring hydrogen storage material hydrogen both at home and abroad is that the main method of P-C-T curve has gravimetric method, constant volume method, constant volume pressure differential method and constant volume differential flowmeter method etc.These methods all are to measure the change curve of hydrogen pressure with the material hydrogen under steady temperature, so the general designation constant temperature method.Wherein, constant volume method is realized and has degree of precision being widely adopted because of its method simply, easily.
Present hydrogen storage material has metal hydride class hydrogen storage material, complex hydrides class hydrogen storage material and absorption class hydrogen storage material etc.And metal-organic framework materials is a kind of novel porosint, because of its have high permeability, specific surface area big, synthetic convenient, the skeleton scale is variable and can make advantages such as chemical modification, structure be abundant according to target call is considered to one of hydrogen storage material that has most storage hydrogen prospect.
At present, both at home and abroad only to some metal-organic framework materials respectively the hydrogen storage property under (77K), normal temperature and high temperature under the liquid nitrogen temperature study, but do not have (the research of metal-organic framework materials hydrogen storage property in the scope of 77K~300K) of wide warm area.So, do not have corresponding test unit yet.Therefore, (wide temperature zone hydrogen storage material low temperature hydrogen storage performance testing device in the scope of 77K~300K), (the hydrogen storage property research in the scope of 77K~300K) is necessary and far reaching at wide warm area to metal-organic framework materials to design wide warm area.
Summary of the invention
In order to remedy the deficiency of prior art, the invention provides a kind of research metal-organic framework materials at the wide warm area (wide temperature zone hydrogen storage material low temperature hydrogen storage performance testing device of low temperature hydrogen storage property in the scope of 77K~300K).In process of the test, test unit as cooling working medium, and is realized the wide warm area (adjustment in the scope of 77K~300K) in conjunction with electrical heating with circulating liquid nitrogen.The PID temperature controller is regulated the heat that adds of heater strip by the temperature signal that thermopair records.Pressure transducer and temperature acquisition instrument with the data transmission that records to data acquisition system (DAS).Flange of sample room is arranged in the bottom, sample chamber, and interior Dewar is integrally welded with outer Dewar flange, to guarantee the replacing of sample.
The present invention is achieved through the following technical solutions.
The present invention includes Dewar container for liquefied nitrogen, high pressure hydrogen steel cylinder, vacuum unit, data acquisition computer, temperature acquisition instrument, PID temperature controller, flange, platinum-resistance thermometer, sample chamber, heater strip, cooling coil, thermopair, interior Dewar, outer Dewar, vacuum gauge, pressure transducer and valve.Wherein, the sample chamber places interior Dewar, interior Dewar places in the outer Dewar with outer Dewar flange is integrally welded, and form vacuum interlayer with outer Dewar, heater strip and cooling coil alternately are wrapped on the outer wall of sample chamber and interior Dewar respectively, thermopair is installed in respectively on the outer wall of sample chamber and interior Dewar, and platinum-resistance thermometer is installed in the top of sample chamber, and flange of sample room is arranged in the bottom of sample chamber; First safety valve and pressure transducer are installed on the output channel of high pressure hydrogen steel cylinder, second safety valve is installed on the interior Dewar flange, the 3rd safety valve and vacuum gauge are installed on the outer wall of outer Dewar, and outer Dewar vacuumizes valve by second and is connected with the vacuum unit.
The output terminal of Dewar container for liquefied nitrogen is connected with the import that the second liquid nitrogen transfer valve and sample chamber reach the cooling coil on the interior Dewar outer wall by the first liquid nitrogen transfer valve respectively, and the outlet of cooling coil communicates with atmosphere by the first liquid nitrogen exhaust valve and the second liquid nitrogen exhaust valve respectively; The outlet of high pressure hydrogen steel cylinder is divided into two-way after filling valve by hydrogen, first vacuum pumping valve of leading up to is connected with the vacuum unit, another road is divided into two-way again, and the hydrogen vent valve of leading up to communicates with atmosphere, and the top of Dewar flange and sample chamber was inserted in the sample chamber in another road was passed; Heater strip all is connected with the PID temperature controller with thermopair; Data acquisition computer is connected with platinum-resistance thermometer by the temperature acquisition instrument; Pressure transducer is connected with data acquisition computer.
Before on-test, the metal-organic framework materials sample needs through vacuum stripping and activation processing, to remove the foreign gas of material surface absorption, improves the material surface activity.At first, take by weighing the sample chamber that an amount of sample is put into test unit, and sealing.Close hydrogen vent valve, the first liquid nitrogen transfer valve and the second liquid nitrogen transfer valve, the first liquid nitrogen exhaust valve and the second liquid nitrogen exhaust valve and second vacuum pumping valve then, open hydrogen and fill the valve and first vacuum pumping valve, open the vacuum unit sample chamber and pipeline are vacuumized.When reaching the vacuum requirement, close vacuum unit, first vacuum pumping valve and hydrogen and fill valve, and then slowly open the filled valve of hydrogen.High-purity hydrogen is housed in the hydrogen gas cylinder, and quantitatively hydrogen fills valve from hydrogen gas cylinder through hydrogen and enters into the sample chamber.After the suction H-H reaction of a period of time, open first vacuum pumping valve, and utilize heater strip that the sample chamber is heated simultaneously, and open the vacuum unit sample chamber and pipeline are vacuumized, make and close vacuum unit, first vacuum pumping valve, hydrogen behind the sample releasing hydrogen gas and fill valve and heater strip.And then slowly open the filled valve of hydrogen, and so repeating 3~8 times, the rate of pressure change each up to sample tends towards stability.
After sample fully activates, just can begin the measurement of metal-organic framework materials hydrogen.At first, open the first liquid nitrogen transfer valve and the second liquid nitrogen transfer valve, the first liquid nitrogen exhaust valve and the second liquid nitrogen exhaust valve, pure liquid nitrogen is housed in the Dewar container for liquefied nitrogen, liquid nitrogen from Dewar container for liquefied nitrogen in the first liquid nitrogen transfer valve and the second liquid nitrogen transfer valve flow into cooling coil on sample chamber and the interior Dewar outer wall respectively, after the first liquid nitrogen exhaust valve and the second liquid nitrogen exhaust valve enter atmosphere.Turn-on data collecting computer and temperature acquisition instrument are opened the PID temperature controller, and the temperature signal that records by thermopair utilizes the PID temperature controller that the heat that adds of heater strip is regulated.Open first vacuum pumping valve, second vacuum pumping valve and hydrogen simultaneously and fill valve, open the vacuum unit.When system temperature constant in appointment probe temperature and reach vacuum and require after, close the vacuum unit and first vacuum pumping valve, second vacuum pumping valve and hydrogen and fill valve, and then slowly open hydrogen and fill valve, make quantitative hydrogen fill valve through hydrogen and enter in the sample chamber from hydrogen gas cylinder, and by pressure transducer and data acquisition computer record force value at this moment.Through suction H-H reaction after a while, when sample suction hydrogen finishes,, and close the filled valve of hydrogen once more by pressure transducer and data acquisition computer record force value at this moment.And then slowly open the filled valve of hydrogen, repeat aforesaid operations, till sample suction hydrogen is saturated.
Inhale after the end of hydrogen process, sample is in saturated suction hydrogen state, and reaches dehydrogenation condition.At this moment, open the hydrogen vent valve, intrasystem hydrogen enters atmosphere through the hydrogen vent valve.After quantitative hydrogen enters atmosphere, close the hydrogen vent valve rapidly, and by pressure transducer and data acquisition computer record force value at this moment.Through hydrogen discharge reaction after a while, when sample is put hydrogen and is finished, the force value by pressure transducer and data acquisition computer record this moment once more.And then open the hydrogen vent valve, repeat aforesaid operations, till sample is put hydrogen fully.
Other conditions are constant, utilize the PID temperature controller that the heat that adds of heater strip is regulated, change the temperature of sample chamber, repeat whole suction, put the hydrogen process of the test, just can record metal-organic framework materials and (reach the low temperature hydrogen storage property under the different pressures in the scope of 77K~300K) at wide warm area.
After a kind of low temperature hydrogen storage property test of metal-organic framework materials is finished, close all appts and equipment.By unloading outer Dewar flange, interior Dewar flange and flange of sample room successively, just can carry out the replacing of sample.After having changed sample, install flange of sample room, interior Dewar flange and outer Dewar flange more successively, other conditions are constant, repeat whole suction, put the hydrogen process of the test, just can record the different metal organic framework material at wide warm area (in the scope of 77K~300K) and the low temperature hydrogen storage property under the different pressures.
Beneficial effect of the present invention: the present invention as cooling working medium, and realizes wide warm area (adjustment and control in the scope of 77K~300K) in conjunction with electrical heating with circulating liquid nitrogen.Interior Dewar and sample chamber outer wall all are wound with heater strip and cooling coil, and the PID temperature controller is regulated the heat that adds of heater strip by the temperature signal that thermopair records, and can make the faster more stable required probe temperature that reaches of system, reduce the test required time.And this apparatus structure is simple, is easy to make, and has better economic.Another characteristics of the present invention are that flange of sample room is arranged in the bottom, sample chamber, and interior Dewar is integrally welded with outer Dewar flange, can guarantee the replacing of sample like this.
Description of drawings
Fig. 1 is a wide temperature zone hydrogen storage material low temperature hydrogen storage performance testing device structural representation of the present invention.
Among the figure: 1 Dewar container for liquefied nitrogen, 2 high pressure hydrogen steel cylinders, 3 vacuum units, 4 data acquisition computers, 5 temperature acquisition instrument, the 6PID temperature controller, Dewar flange in 7,8 outer Dewar flanges, 9 platinum-resistance thermometers, 10 sample chambers, 11 flange of sample room, 12 heater strips, 13 cooling coils, 14 thermopairs, Dewar in 15,16 outer Dewars, 17 vacuum gauges, 18 pressure transducers, V1 hydrogen fills valve, V2 first vacuum pumping valve, V3 hydrogen vent valve, the V4 first liquid nitrogen transfer valve, the V5 first liquid nitrogen exhaust valve, the V6 second liquid nitrogen transfer valve, the V7 second liquid nitrogen exhaust valve, V8 second vacuum pumping valve, V9 first safety valve, V10 second safety valve, V11 the 3rd safety valve.
Embodiment
Below in conjunction with accompanying drawing concrete enforcement of the present invention is further described.
As shown in Figure 1, the present invention includes Dewar container for liquefied nitrogen 1, high pressure hydrogen steel cylinder 2, vacuum unit 3, data acquisition computer 4, temperature acquisition instrument 5, PID temperature controller 6, interior Dewar flange 7, outer Dewar flange 8, platinum-resistance thermometer 9, sample chamber 10, flange of sample room 11, heater strip 12, cooling coil 13, thermopair 14, interior Dewar 15, outer Dewar 16, vacuum gauge 17, pressure transducer 18, hydrogen fills valve V1, the first vacuum pumping valve V2, hydrogen vent valve V3, the first liquid nitrogen transfer valve V4, the first liquid nitrogen exhaust valve V5, the second liquid nitrogen transfer valve V6, the second liquid nitrogen exhaust valve V7, the second vacuum pumping valve V8, the first safety valve V9, the second safety valve V10, the 3rd safety valve V11.Wherein Dewar container for liquefied nitrogen 1, high pressure hydrogen steel cylinder 2, vacuum unit 3 all are placed on the ground, laboratory.Data acquisition computer 4, temperature acquisition instrument 5, PID temperature controller 6, outer Dewar 16 are placed on the experimental implementation platform.Sample chamber 10 places interior Dewar 15, interior Dewar 15 and outer Dewar flange 8 integrally welded placing in the outer Dewar 16, and form vacuum interlayers with outer Dewar 16, heater strip 12 and cooling coil 13 alternately are wrapped in respectively on the outer wall of sample chamber 10 and interior Dewar 15, thermopair 14 is installed in respectively on the outer wall of sample chamber 10 and interior Dewar 15, platinum-resistance thermometer 9 is installed in the top of sample chamber 10, and flange of sample room 11 is arranged in the bottom of sample chamber 10; The first safety valve V9 and pressure transducer 18 are installed on the output channel of high pressure hydrogen steel cylinder 2, the second safety valve V10 is installed on the interior Dewar flange 7, the 3rd safety valve V11 and vacuum gauge 17 are installed on the outer wall of outer Dewar 16, and outer Dewar 16 vacuumizes valve V8 by second and is connected with vacuum unit 3.
The output terminal of Dewar container for liquefied nitrogen 1 is connected with the import that sample chamber 10 reaches the cooling coil 13 on interior Dewar 15 outer walls with the second liquid nitrogen transfer valve V6 by the first liquid nitrogen transfer valve V4 respectively, and the outlet of cooling coil 13 communicates with atmosphere by the first liquid nitrogen exhaust valve V5 and the second liquid nitrogen exhaust valve V7 respectively; The outlet of high pressure hydrogen steel cylinder 2 is divided into two-way after filling valve V1 by hydrogen, the first vacuum pumping valve V2 of leading up to is connected with vacuum unit 3, another road is divided into two-way again, the hydrogen vent valve V3 of leading up to communicates with atmosphere, and 10 tops of Dewar flange 7 and sample chamber were inserted in the sample chamber 10 in another road was passed; Heater strip 12 all is connected with PID temperature controller 6 with thermopair 14; Data acquisition computer 4 is connected with platinum-resistance thermometer 9 by temperature acquisition instrument 5; Pressure transducer 18 is connected with data acquisition computer 4.
Before on-test, the metal-organic framework materials sample needs through vacuum stripping and activation processing, to remove the foreign gas of material surface absorption, improves the material surface activity.At first, take by weighing the sample chamber 10 that an amount of sample is put into test unit, and sealing.Close hydrogen vent valve V3, the first liquid nitrogen transfer valve V4 and the second liquid nitrogen transfer valve V6, the first liquid nitrogen exhaust valve V5 and the second liquid nitrogen exhaust valve V7 and the second vacuum pumping valve V8 then, open hydrogen and fill the valve V1 and the first vacuum pumping valve V2, open 3 pairs of sample chambers 10 of vacuum unit and pipeline and vacuumize.When reaching the vacuum requirement, close vacuum unit 3, the first vacuum pumping valve V2 and hydrogen and fill valve V1, and then slowly open the filled valve V1 of hydrogen.In the hydrogen gas cylinder 2 high-purity hydrogen is housed, quantitatively hydrogen fills valve V1 from hydrogen gas cylinder 2 through hydrogen and enters into sample chamber 10.After the suction H-H reaction of a period of time, open the first vacuum pumping valve V2, and utilize 12 pairs of sample chambers of heater strip 10 to heat simultaneously, open 3 pairs of sample chambers 10 of vacuum unit and pipeline and vacuumize, make and close vacuum unit 3, the first vacuum pumping valve V2, hydrogen behind the sample releasing hydrogen gas and fill valve V1 and heater strip 12.And then slowly open the filled valve V1 of hydrogen, and so repeating 3~8 times, the rate of pressure change each up to sample tends towards stability.
After sample fully activates, just can begin the measurement of metal-organic framework materials hydrogen.At first, open the first liquid nitrogen transfer valve V4 and the second liquid nitrogen transfer valve V6, the first liquid nitrogen exhaust valve V5 and the second liquid nitrogen exhaust valve V7, pure liquid nitrogen is housed in the Dewar container for liquefied nitrogen 1, liquid nitrogen from Dewar container for liquefied nitrogen 1 in the first liquid nitrogen transfer valve V4 and the second liquid nitrogen transfer valve V6 flow into cooling coil 13 on sample chamber 10 and interior Dewar 15 outer walls respectively, after the first liquid nitrogen exhaust valve V5 and the second liquid nitrogen exhaust valve V7 enter atmosphere.Turn-on data collecting computer 4 and temperature acquisition instrument 5 are opened PID temperature controller 6, and the temperature signal that records by thermopair utilizes the heat that adds of 6 pairs of heater strips 12 of PID temperature controller to regulate.Open the first vacuum pumping valve V2, the second vacuum pumping valve V8 and hydrogen simultaneously and fill valve V1, open vacuum unit 3.When system temperature constant in appointment probe temperature and reach vacuum and require after, close the vacuum unit 3 and the first vacuum pumping valve V2, the second vacuum pumping valve V8 and hydrogen and fill valve V1, and then slowly open hydrogen and fill valve V1, make quantitative hydrogen fill valve V1 through hydrogen and enter in the sample chamber 10 from hydrogen gas cylinder 2, and by pressure transducer 18 and data acquisition computer 4 records force value at this moment.Through suction H-H reaction after a while, when sample suction hydrogen finishes,, and close the filled valve V1 of hydrogen once more by pressure transducer 18 and data acquisition computer 4 records force value at this moment.And then slowly open the filled valve V1 of hydrogen, repeat aforesaid operations, till sample suction hydrogen is saturated.
Inhale after the end of hydrogen process, sample is in saturated suction hydrogen state, and reaches dehydrogenation condition.At this moment, open hydrogen vent valve V3, intrasystem hydrogen enters atmosphere through hydrogen vent valve V3.After quantitative hydrogen enters atmosphere, close hydrogen vent valve V3 rapidly, and by pressure transducer 18 and data acquisition computer 4 records force value at this moment.Through hydrogen discharge reaction after a while, when sample is put hydrogen and finished, once more by pressure transducer 18 and the data acquisition computer force value of 4 record this moments.And then open hydrogen vent valve V3, repeat aforesaid operations, till sample is put hydrogen fully.
Other conditions are constant, utilize the heat that adds of 6 pairs of heater strips 12 of PID temperature controller to regulate, change the temperature of sample chamber 10, repeat whole suction, put the hydrogen process of the test, just can record metal-organic framework materials and (reach the low temperature hydrogen storage property under the different pressures in the scope of 77K~300K) at wide warm area.
After a kind of low temperature hydrogen storage property test of metal-organic framework materials is finished, close all appts and equipment.By unloading outer Dewar flange 8, interior Dewar flange 7 and flange of sample room 11 successively, just can carry out the replacing of sample.After having changed sample, install flange of sample room 11, interior Dewar flange 7 and outer Dewar flange 8 more successively, other conditions are constant, repeat whole suction, put the hydrogen process of the test, just can record the different metal organic framework material at wide warm area (in the scope of 77K~300K) and the low temperature hydrogen storage property under the different pressures.